Optics system for an interferometer that uses a measuring mirror, a reference mirror and a beam deflector

Abstract

An optical assembly of an interferometer that includes a beam splitter for dividing the beams emitted by a radiation source into at least one measuring and one reference beam and at least one measuring and one reference mirror, on which the measuring and the reference beams impinge, wherein at least one of the mirrors can be displaced along a measuring axis. The optical assembly further includes a beam deflector, as well as a retro-reflector, wherein the measuring and the reference beams reflected at the measuring and the reference mirrors via the beam deflector and the retro-reflector are guided at least a second time in the direction toward the measuring and the reference mirrors and wherein the beam deflector is embodied as a plane-parallel plate.

1. An optical assembly of an interferometer, comprising:
 a beam splitter for dividing the beams emitted by a radiation source into at least one measuring and one reference beam; 
 at least one measuring and one reference mirror, arranged along at least two measuring axes, on which the measuring and the reference beams impinge, respectively, wherein respectively at least one of the mirrors is displaceable along a respective one of the at least two measuring axes; 
 a beam deflector, as well as a retro-reflector, wherein the measuring and the reference beams reflected at the measuring and the reference mirrors are received by both the beam deflector and the retro-reflector and are guided by the beam deflector and the retro-reflector at least a second time in a direction toward the measuring and the reference mirrors; 
 an axis splitter, arranged between the beam deflector and the retro-reflector, which divides the measuring and the reference beams so as to be parallel to the at least two measuring axes, wherein the axis splitter comprises at least one plane-parallel plate. 
 
   
   
     2. An interferometer, comprising:
 a radiation source; 
 an optical assembly comprising:
 a beam splitter for dividing the beams emitted by a radiation source into at least one measuring and one reference beam; 
 at least one measuring and one reference mirror, arranged along at least two measuring axes, on which the measuring and the reference beams impinge, respectively, wherein respectively at least one of the mirrors is displaceable along a respective one of the at least two measuring axes; 
 a beam deflector, as well as a retro-reflector, wherein the measuring and the reference beams reflected at the measuring and the reference mirrors are received by both the beam deflector and the retro-reflector and are guided by the beam deflector and the retro-reflector at least a second time in the direction toward the measuring and the reference mirrors; 
 an axis splitter, arranged between the beam deflector and the retro- reflector, which divides the measuring and the reference beams so as to be parallel to the at least two measuring axes, wherein the axis splitter comprises at least one plane-parallel plate; 
 at least two detectors, on which the measuring and the reference beams impinge following the second reflection at the measuring and the reference mirrors in the at least two measuring axes, wherein one of the at least two detectors generates an output signal as a function of a displacement of the measuring mirror relative to one of the at least two measuring axes and another one of the at least two detectors generates an output signal as a function of a displacement of the measuring mirror relative to another of the at least two measuring axes. 
 
 
   
   
     3. An optical assembly of an interferometer, comprising:
 a beam splitter for dividing the beams emitted by a radiation source into a measuring and a reference beam; 
 at least one measuring and one reference mirror, arranged along at least two measuring axes, on which the measuring and the reference beams impinge, respectively, wherein respectively at least one of the mirrors is displaceable along a respective one of the at least two measuring axes; 
 a beam deflector, as well as a retro-reflector, wherein the measuring and the reference beams reflected at the measuring and the reference mirrors are received by both the beam deflector and the retro-reflector and are guided by the beam deflector and the retro-reflector at least a second time in the direction toward the measuring and the reference mirrors; 
 an axis splitter, arranged between the beam deflector and the retro-reflector, which divides the measuring and the reference beams so as to be parallel to the at least two measuring axes, wherein a measuring and a reference mirror is co-linearly arranged along each of the at least two measuring axes. 
 
   
   
     4. An interferometer, comprising:
 a radiation source; 
 an optical assembly comprising:
 a beam splitter for dividing the beams emitted by a radiation source into a measuring and a reference beam; 
 at least one measuring and one reference mirror, arranged along at least two measuring axes, on which the measuring and the reference beams impinge, respectively, wherein respectively at least one of the mirrors is displaceable along a respective one of the at least two measuring axes; 
 a beam deflector, as well as a retro-reflector, wherein the measuring and the reference beams reflected at the measuring and the reference mirrors are received by both the beam deflector and the retro-reflector and are guided by the beam deflector and the retro-reflector at least a second time in the direction toward the measuring and the reference mirrors; 
 an axis splitter, arranged between the beam deflector and the retro-reflector, which divides the measuring and the reference beams so as to be parallel to the at least two measuring axes, wherein a measuring and a reference mirror is co-linearly arranged along each of the at least two measuring axes; and 
 at least two detectors, on which the measuring and the reference beams impinge following the second reflection at the measuring and the reference mirrors in the at least two measuring axes, wherein one of the at least two detectors generates an output signal as a function of a displacement of the measuring mirror relative to one of the at least two measuring axes and another one of the at least two detectors generates an output signal as a function of a displacement of the measuring mirror relative to another of the at least two measuring axes.